gingrich did it with wrong king of cnn and our own juan williams during the republican primaries. our senior political analyst brit hume has been in this position. here is his take on the job difficulties. >> you are at the center of attention but you don't want to be. you want the candidate to be the story, you want to facilitate that. you have to be firm enough and sharpen your questioning enough so it makes for an interesting debate and be careful not to cross the line to where it looks like you are favoring one candidate over another. >>jonathan: he says he things it is unlikely the candidates themselves will attack the moderator tonight because he says while that may happen in a primary contest it is far less likely to happen with these candidates trying to look presidential tonight. >>shepard: there is criticism over a lack of racial diversity. >>jonathan: just divertity in general. you look at the moderators of the presidential debate, candy, in the middle, from cnn, is the first woman moderator of a presidential debate for something like 20 years. juan williams says there